An image forming apparatus that is capable to form an image on both front and back surfaces of a sheet has a function of switching back a conveying direction of a sheet in which an image is formed on one surface thereof and sending the sheet to an image forming section again.
In the image forming apparatus that is capable to form an image on both front and back surfaces of a sheet, a conveying path for sending a sheet in which an image is formed on one surface thereof to the image forming section again may be required. Accordingly, the external dimension of the image forming apparatus is likely to increase. However, a further decrease in external dimension is required for the image forming apparatus.